The invention relates to an optoelectronic component implemented in Si technology having a quantum-well structure with at least one pseudomorphously formed SiGe layer forming a quantum well in the valence band structure between layers made from Si and/or SiGe.
The invention is used, inter alia, for the production of infrared detectors using Si technology.
Known silicon/germanium infrared (IR) detectors are based on the principle of heterointernal photoemission (HIP; see, e. g., J. Lin et al., OPTICAL ENGINEERING, Vol. 33, p. 716, 1994; B. Y. Tsaur et al., OPTICAL ENGINEERING, Vol. 33, p. 72, 1994), In a highly p-doped (p&gt;5.multidot.10.sup.20 cm.sup.-3) SiGe layer, which is epitaxially grown on an undoped Si layer, the defect electrons (holes) disposed on the acceptor atoms are optically excited from the SiGe quantum well and transported towards the contacts by means of an externally applied electrical field and thus cause current to flow. However, these structures have several drawbacks because of the high doping of the SiGe wells. In particular:
a) for multiple quantum-well structures, the Coulomb scattering and recombination processes of the charge carriers previously photogenerated and drifting to the contacts are increased at the charged ion cores in the SiGe well, and thus, the efficiency of such multiple quantum-well structures is low due to the increased recombination probability; PA1 b) the optical transition selection rules are cancelled in the SiGe well, thus, the optical excitations of the localized holes in the SiGe well have a relatively small oscillation strength; and, PA1 c) the epitaxial quality of the SiGe/Si hetero-interface is greatly impaired because of the high doping in the quantum well by boron diffusion and segregation.
Therefore, it is the object of the invention to provide an optoelectronic component with a quantum-well structure by means of which component a high quantum efficiency and thus detection sensitivity can be accomplished.